FIG. 8 shows a sectional view of a conventional drum type washing machine, and FIG. 9 shows a block diagram of the conventional drum type washing machine. As shown in FIGS. 8 and 9, a rotating drum 1 has a plurality of perforations 2 on its outer circumference and is rotatably disposed in a tub 3. A rotating shaft 4 is located substantially horizontal to a rotating axis of the rotating drum 1. A motor 5 is connected to the rotating shaft 4 and rotates the rotating drum 1. A few protrusions 6 are formed at an inner wall of the rotating drum 1.
The tub 3 is sustained in a cabinet 7 by a spring means 8. One end of a drain hose 9 is connected to a lower part of the tub 3, and another end of the drain hose 9 is connected to a drain pump 10, thereby draining used water. A feed valve 11 supplies water into the tub 3, and a water level detecting means 12 detects a water level in the tub 3.
A controller 13 having a controlling means 14, which is formed of a micro-computer, operates the motor 5, the drain pump 10, the feed valve 11 and the like via a power switching means 15, thereby controlling sequential processes such as washing, rinsing or liquid-extracting. An operating course and the like is inputted by an inputting means 16. The controlling means 14 displays information at a display means 17, based on information from the inputting means 16, thereby informing an operator of the inputted information. A memory 18 stores necessary data in order for the controlling means 14 to control. The reference numeral 19 denotes a power source, and the reference numeral 20 denotes a power switch.
An operation of a washing process is described hereinafter. After a laundry, such as clothes or textiles, and detergent are put into the rotating drum 1, the washing process starts by pushing a power source button and a start button (not shown). Then the feed valve 11 supplies water. When the water level detecting means 12 detects a predetermined water level N1, the motor 5 drives. When the water level detecting means 12 detects a predetermined water level N2, supplying water is stopped. The water level N2 is not lower than the water level N1.
In the washing process, the laundry absorbs water, therefore water is supplied to the rotating drum 1. While water is supplied, the rotating drum 1 rotates in normal direction, stops, rotates in reverse direction and stops using the motor 5 at a predetermined number of revolutions and a predetermined time. The laundry is caught on the protrusions 6, lifted and fallen in water from around an upper side of the rotating drum 1. By this working mentioned above, detergent is gradually dissolved in water to create washing liquid, whereby the washing liquid acts on stains of the laundry. After the washing process is finished, the drain pump 10 drains the washing liquid in the tub 3.
As discussed above, the conventional drum type washing machine washes the laundry using mechanical force, while detergent in the rotating drum 1 is dissolved by rotating in a first direction, stopping, rotating in a reverse direction and stopping of the rotating drum 1.
However, the conventional drum type washing machine does not use much water. Thus, much time may be required for dissolving the detergent and for getting the laundry wet uniformly by detergent water. As a result, unevenness caused by washing occurs, detergency deteriorates or washing time becomes longer.